Doug Ford will be forever linked with his tumultuous brother Rob.

Rob Ford had left the picture, forced by a cancer diagnosis to abandon his 2014 bid for re-election as Toronto’s mayor. But one of the late-night shows that helped make him an international celebrity, for all the wrong reasons, had discovered a convenient replacement.

Doug Ford was running in his younger brother’s place and already making embarrassing gaffes, charged John Oliver on Last Week Tonight.

“Toronto,” the comedian said with an impish grin. “Please, please elect this man . . . Let us laugh at your a--hole for another four years.”

Doug Ford was unsuccessful in that mayoral bid, but now he’s near the end of a campaign for leader of the Ontario Progressive Conservatives, with some notable achievements under his belt.

His policy pronouncements have been echoed by his rivals, he’s travelled tirelessly around the province and presented a stable face for a party beset by chaos.

But to many, Ford is linked with his late brother’s tumultuous, scandal-filled term as mayor. Doug Ford was a city councillor at the time and his brother’s relentless champion, even after the mayor admitted to smoking crack cocaine.

Ford’s biggest challenge may be overcoming that — and a reputation as a political bull in a china shop.

And yet, rather than shrink from those years, Ford has made them part of his campaign. He points out he and his brother eliminated an unpopular city tax and cut costs in ways applicable to the debt-laden provincial government.

“If you are asking me if I would stick up for my brother again, I would do it in a heartbeat,” Ford told the debate moderator.

Until Patrick Brown resigned as Tory leader last month, Ford had planned to run for mayor again.

He became the first leadership candidate to say he would rescind Brown’s’s plan to introduce a carbon tax. He also led the way in suggesting a revamp of the Liberals’ sex-­education curriculum.

“He’s not going to be led by the nose by either insiders or outsiders,” says supporter Frank Klees, a former Conservative cabinet minister. “He’s going to do the right thing because it’s the right thing to do.”

Ford’ is part of a political dynasty.Doug Sr. in 1995 won a seat in the provincial legislature as part of Mike Harris’s PC government. Rob was elected to Toronto city council in 2000 and when he launched his 2010 mayoral bid, Doug ran for city council in Rob’s old ward.

They harnessed voter resentment of “elites” although the Fords grew up in a mansion and Doug Jr. inherited his father’s business.

At city hall, he had trouble adjusting to a more constrained role.

“He believed the bureaucracy existed to serve the mayor, or in this case the Ford family. That if you were the mayor’s brother, you could kind of assert yourself as co-mayor,” said former colleague John Filion.

Ford also attracted controversy: a tiff with Margaret Atwood over library closings; a proposal for a monorail and Ferris wheel at Toronto’s waterfront; and a rebuke from the city’s ethics commissioner for his advocacy of a company connected to his business.

In 2013, there were allegations Ford had been a teenaged drug dealer (which he vehemently denies).

Ford could be “very affable” at city hall. But only to a point. “He’s a total jerk . . . if he doesn’t get his way. That’s when he gets mean,” said an ex-staffer who asked for anonymity. “He just gets angry.”

Ford lashed out at journalists, accusing them of lying, when reports surfaced of a video of his brother smoking crack. He accused police chief Bill Blair of leaking a court document with embarrassing information about the mayor because of cuts to the force’s budget.

Some critics have suggested Doug enabled his brother’s addiction. But Klees sees his support as a sign of character.

“Notwithstanding what demons his brother may have been facing, here’s a man who stood by,” Klees said. “They knew how to balance a budget, they knew how to manage the taxpayers’ dollars. They knew how to prioritize services. That’s the legacy we should be looking at.”

Even critics do not discount Doug’s potential for success. “He really has that survival instinct, that crocodile brain,” says Filion.